ClassManagernem | Help Work and Energy Part 3 Begin Date: 4/1/2022 12:01:00 AM -- Due Date: 4122/2022 11:59:00 PM End Date: 5115(2022 11:59:00 PM (10%) Problem 10: Consider the forces involved in doing push-ups. The woman's weight acts as a force exerted downward on her center of gravity (marked CG in the gure). You may assume that the angle between her body and the oor is small enough so that the small angle approximation is valid throughout this motion. 'Utlleexpt-rtlaxom D A 33% Part (3) Calculate the force, in newtons, the woman in the gure exerts to do a pushup at constant speed. Grade Summary F r = I Deductions 0% Potential 100% Submissions Attempts remaining: (% per attempt) detailed view Degrees O Radians Submit Hint I give up! Hints: 0% deduction per hint. Hints remaining: 1 Feedback: 0% deduction per feedback. E a 33% Part (b) How much work, in joules, does she do if her center of mass rises 0.25 m? E A 33% Part (c) What is her useful power output, in watts, if she does 22 push-ups in 1 min? Ignore any work done during the downward motion. ClassManagemenl | Help Work and Energy Part 3 Begin Date: 4/1i2022 12:01:00 AM -- Due Date: 4/22/2022 11:59:00 PM End Date: 5/15/2022 11:59:00 PM (10%) Problem 4: Acrate of mass m is initially at rest at the peak of an inclined plane, which has y a height of 6.4 in and makes an angle of 6 = 21 with respect to the horizontal. After it has been released, it is observed to be moving at v = 0.95 m/s 3 distance d after the end of the inclined plane as shown. The coefcient of kinetic friction between the crate and the plane is ,up = 0.1 , and the coefcient of friction on the horizontal surface is u, = 0.2. thccxpcrtta.com D 3 Find the distance d, in meters. Grade Summary d = | Deductions 0% Potential 100% Submissions Attempts remaining: (% per attempt) detailed view tanhO Degrees O Radians Submit Hint I give up! Hints: 0% deduction per hint. Hints remaining: 1 Feedback: 0% deduction per feedback. Work and Energy Part 3 Begin Date: 4/1/2022 12:01:00 AM - Due Date: 4/22/2022 11:59:00 PM End Date: 5/15/2022 11:59:00 PM (10%) Problem 1: Amass is sliding on a frictionless surface with a speed v. It runs into a linear X spring with a spring constant of k, which compresses from position xi to position xr- v "\" - :x' I l l l . Kr I Utllecxpcrttaxum E A 25% Part (a) Write a general expression for the force that the spring exerts on the mass, in term of k and x. Choose the initial position of the front of the spring to be xi=0. E g7 25% Part (b) Select the equation that correctly describes the work done by the spring to stop the mass. W = - Lixfk x dx I/ Correct! E k 25% Part (c) Evaluate the relationship in part (b) to arrive at an expression for the work done in terms of known variables. a: A 25% Part (d) Solve for the numerical value of the work done in Joules given that xi = 0, xf = 44 cm, and k = 75 N/m. Grade Summary W= l Deductions 0% Potential 100% Submissions Attempts remaining: 5 (% per attempt) detailed view Degrees O Radians JO BACKSPACE DEL CLEAR Submit Hint Feedback I give up! Hints: 0% deduction per hint. Hints remaining: 1 Feedback: 0% deduction per feedback